Sunk Cost Fallacy

What is it?

The sunk cost fallacy is the tendency to continue a behavior or endeavor because of resources already invested (time, money, effort) rather than by weighing its future value. Standard economic reasoning says sunk costs should be ignored, since they cannot be recovered whatever you choose next. People struggle with this because of loss aversion and a need to justify past decisions. The fallacy is stronger when the investment is visible to others, which makes it harder to admit "failure" by stopping. A classic case is the Concorde (hence the "Concorde fallacy"): the British and French governments kept funding the supersonic airliner long after its commercial prospects looked poor. In personal life, it shows up as staying in unfulfilling relationships, finishing bad books, or eating food you don't want just because you paid for it. Organizations often escalate commitment to failing projects, throwing good money after bad. Breaking free means reframing the decision: ask not "how can I justify what I've spent?" but "if I were starting fresh today, would I choose this path?"